On the Tides of the Western Coast of the United States. 3 
lunar hours. When the declination of the moon is at its max- 
imum, the difference in the heights of consecutive high and low » 
Waters is nearly at its maximum; and when the declinatio a 
nearly zero, the difference is the smallest. ee 
The diurnal inequality in the interval is also perf etly well 
marked in these tides, amounting when greatest, to about two 
hours for high water, and one hour and eleven minutes for low 
Ww 
er, 
* 
of graphical corrections in the mode used by Mr. Whewell. 
The ordinates of the diagrams Nos. 1 and 2, (diagram B,) cor- 
respond to the lunitidal intervals, and of Nos. 3 and 4 to the 
heights—the abcisse, in each case, to the hours of the moon’s 
transit. The scale is shown at the top and side of each diagram. 
No. 1, diagram B, shows the results for the half-monthly inequal- 
ity of interval of high water, and the curves traced by them; No. 
2 the same for low water; No. 3eshows the half-monthly inequal- 
ity in the height of high water, and No. 4 in that of low water ; 
the dots show where the observations fall. The comparison of 
the curves, with observations, is given in the annexed table: 
TABLE No. 1. 
Comparison of approximate curves of half-monthly inequality of the tides at Rincon 
Point, with observations. 
eee 
Moon’s INTERVAL. HEIGHT. Moon’s |[ 
“ee. | High water, | Low water. High water. } Low water. age. 
Transit F| From |Observ’n.| From Peas From jObserv’8. | From Obsery’d. lnansit F. 
"| curve Iry curve, | Curve. | curve.| Curve. | curve.| Curve. 
ss M. Ft. Ft Ft. Ft. H, M. 
0 30/11 59] -—10 11745} — 9 | 790} — 3 | 302; +8 | 0 30 
1 30 36| — 2 37| ood 6 | +4) lo} — 8: }.1 80 
2 30 24 0 38| baa. 451 +2 {| 20} —20.|, 2 30 
3 30 Q4el 7 24 7 1710} +2] 38) +29 | 3 30 
4 30 98| — 4 98 |i 2 eGo] — 4 | 52] — 6.|. 4 30 
5 30 48/ — 1% 421 18 | %8| +12] 68| —29 | 5 30 
6 30/12 18} — 1 }1805] —1 | 80] —13 | “70} +26 | 6 30 
7 30 438 13 24) — 7 1400} -+00 Sib 1807 8 
8 30 46; —12 33 9 | 30} +15 | 30; —41 | 8 30 
30 39 27} — 6 | 50} —15} 40) +27 | 9 30 
10 30 27; —1 15} — 38 | 69 5 | 26! —19 | 10 30 
11 30 1l 8 {17 57| = 2 so| —4]| 10] +06 | 11 30 
Mean | 12 08 | +27 (17 55| +35 +39 +110 
—39 —40 —1 
__The results, both for intervals and heights, are very good, con- 
sidering the small number of observations (four,) of which each 
isthe mean. The heights are, as usual, less regular than the 
